Hold on one minute. Having been faced with this problem many a time I'll walk you through it. First, if you want to remove a little material from the side of a drill you'll get a tighter hole O.K., but your drill is shot. You can't get a cylindrical surface stoning the flutes of a drill. MSC has a large assortment of special size reamers if you want to go that route. Best way , in my opinion, use heat. What your cutting is 1/4" thick, that's 1/2 a diameter deep. First open the hole to 1/2"or 33/64" diam. Heat the piece up with a heat gun or good hair dryer as hot as you can get it or, put it in the oven @ 425-450 deg. f. for a 1/2 hour. Have everything set up so you don't loose heat when getting ready to drill it. Slowly feed the drill in @ 250 - 300 rpm USING A WAX LUBRICANT on the drill flutes. You'll have a smooth finish and when it cools down to room temp. it should be .0015-.003 smaller then the diameter of the drill. Do a test piece first to check it out. Happy drilling.I need to drill a 17/32" (.5313") through in 1/4" aluminum. The hole needs to be a few thou under 17/32".
Closer to .5300 or .5210"?
Is there a way to touch up the drill on a belt sander so it will drill a smaller hole?
I don't have time to bore the hole and there are no under size 17/32" reamers.
Can this be done? I was thinking that maybe the flutes on the sides of the drills cutting edges can be touched on the belt sander? I know most drills cut over size, so..?
Thanks
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